A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
One cubic foot of gold weighs more than 1,200 pounds!
78
4.5 pounds of sunlight strike the Earth each day.
27
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Pumice is the only rock that floats on water.
14
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39